1. Field of the Invention
The present invention relates to an image pickup device in which image pixels and phase difference pixels are arranged in a matrix shape and an image pickup apparatus including the image pickup device.
2. Description of the Related Art
There has been proposed an image pickup apparatus including an image pickup device in which image pixels and phase difference pixels are arranged in a matrix shape and an image pickup apparatus that performs so-called image plane phase difference AF.
For example, Japanese Patent Application Laid-Open Publication No. 2010-28397 describes a technique for, in an image pickup apparatus including an image pickup device, on an image plane of which phase difference pixels are arranged, performing readout out of a plurality of pixels in a first mode for adding up and reading out signals of any number of pixels including the phase difference pixels and a second mode for thinning out signals of a part of pixels and reading out signals of at least the phase difference pixels. That is, in the first mode for acquiring a movie (including a live view), in order to secure a frame rate, pixel signals are added up (that is, processed to reduce the number of pixel signals to be read out) and read out. On the other hand, in the second mode for performing the phase difference AF, the phase difference pixels are read out without performing the addition of the pixel signals. The phase difference pixels are acquired in the second mode at a ratio of one frame in a predetermined number of frames. Added-up pixel signals for an image in the first mode are acquired in the other frames.